What is Sensory Overload? Causes, Symptoms & How to Manage It

Every single minute, the brain filters thousands of sensory inputs automatically. For most people, this happens without effort, but for some, it doesn’t. It’s estimated that 69% to 90% of autistic people often experience sensory processing differences. 

When the nervous system receives more than it can handle, sensory overload happens. It then responds in the only way it knows how, and it may be seen as a meltdown, tantrum, repetitive behaviour, or shutdown. 

In this blog, we explain what sensory overload is, its common triggers and symptoms, and strategies for caregivers and individuals to calm down when it happens. 

What is Sensory Overload?

The brain perceives the environment through five senses – sight, hearing, smell, touch, and taste. All this information reaches the brain at the same time, but irrelevant inputs often get filtered out automatically. 

But in some people, this filter doesn’t work the same way. Every input competes for attention from the brain. When these overwhelm the brain, it can’t process all the information properly, and it’s commonly called sensory overload. 

The noise level, lights, and everything about the room could have been the same. But if the body’s response changes before the mind can catch up, the person may experience sensory overload. It’s neither an overreaction nor a behaviour choice. It’s simply the brain that can’t process everything at once and wants an exit. 

It can happen to anyone, but it’s more common in autistic individuals and people with ADHD. 

What Causes Sensory Overload? (Common Triggers)

A single cause can’t be isolated for sensory overload. Often, it builds up before the meltdown happens. Anything like a scratchy collar of a school shirt, a different route taken by a school bus, or someone wearing a new perfume can all lead to sensory overload. It depends on the individual. Some of the common triggers are:

• Loud, sudden, or unpredictable noise
• Bright or flickering lights
• Strong smells from food, perfume, cleaning products, etc
• Varying textures in food or clothes
• Too many people in an environment like a crowded mall or a busy restaurant
• Emotional stress
• Fatigue

Often, emotional stress and fatigue can build up and trigger sensory overload even if the environment remains the same. Knowing the symptoms can help a person to calm themselves. 

Common Symptoms of Sensory Overload

While meltdowns during sensory overload are commonly noticed by all, shutdowns often go unnoticed because people become unusually silent. The absence of a response is also a symptom of sensory overload when the brain has decided that it has nothing left to give. 

The sensory overload symptoms vary from one person to another. Generally, these are observed:

• Covering eyes or ears to block input
• Becoming irritated or agitated
• Sudden emotional outbursts, such as laughing very loudly or uncontrollable crying
• Difficulty speaking
• Physical symptoms like headaches, nausea, and tensing up of muscles
• Starting repetitive movement like hand clapping, rocking, etc
• Becoming unresponsive, going quiet, or becoming still
• Trying to escape the situation abruptly

In children, these symptoms are often misunderstood as bad behaviour. A child refusing to enter a school hall because the lights are too bright may be called a difficult child. An adult leaving a social event early may be called rude. The nervous system of a person with sensory overload communicates via behaviour when they can’t express what they feel with words. 

Sensory Overload in Autism vs ADHD

While sensory overload is more common among people with autism or ADHD, the way their brains respond is often varied. In a room with the same lights, sound, smell, and people, sensory overload shows up in a different way. 

For a person with autism, the input keeps coming, but the brain can’t process it all. They may need a corner, a wall, and silence. It can often lead to a shutdown with the person becoming quieter and still. It’s also easy to miss if the caregiver doesn’t pay close attention to common individual behaviour. 

In the case of people with ADHD, the brain doesn’t understand what input to focus on and tries to focus on everything at once. They may keep adjusting the chair because it feels wrong or stop concentrating on their conversation because the conversation that’s happening three seats over is louder for them. They may find it hard to be still. 

Understanding what the sensory overload feels like for the person experiencing it can help caregivers find a way to calm down the response. 

What Does Sensory Overload Feel Like?

The music may not be too loud in the room. But for the person experiencing sensory overload, it might feel like pressing against the inside of their skull. 

They become very uncomfortable as everything around them feels wrong, and they can’t stop noticing it. Someone may ask a question, but they can’t form an answer. Not because they don’t know it, but because the part of the brain that has to assemble the words focuses on something else. 

This dysregulation is what caregivers often miss because it’s challenging to know when the nervous system of a person is at its capacity. When the sensory overload passes, the person continues to experience exhaustion and embarrassment, and recovering from that can also be difficult. 

How to Calm Sensory Overload (Practical Strategies)

Some adults who are aware of their sensory overload triggers and symptoms may be able to calm them down. In most situations, caregivers can intervene to reduce the brain’s workload. Removing the person from the trigger that’s contributing to the sensory overload is the first step. Asking them questions can add to their stress because they are already struggling to process the information they receive. 

Some of the practical strategies to calm sensory overload are:

• Remove or reduce the trigger by leaving the environment, dimming the lights, or turning off music or noise.
• Create a calm-down space, such as a quiet corner at home or school, with minimal sensory input.
• Use noise-cancelling headphones in environments that can’t be avoided or controlled.
• Establish a signal system, such as a word or gesture, that means that the person needs to stop without requiring explanation.
• Tracking behaviour patterns may help identify triggers and plan the day around them.

While it’s not possible to eliminate all difficult environments, building awareness about sensory overload can make it manageable. Professional help is also available to caregivers and patients to manage and navigate symptoms of sensory overload. 

Learning Disability Services in Wolverhampton

Sensory overload is manageable with the right support structure. A trained healthcare professional can identify specific triggers, establish school accommodations, and help adults recognise their own nervous system responses before they escalate. 

Secure Healthcare Solutions offers nurse-led teams trained to recognise complex behavioural and sensory patterns early and respond with structured routines. The care teams create a flexible design that adapts to changes across different life stages.  

Learning disability services in Wolverhampton work with individuals and families to build support around the person. They listen to what the person experiences, what their specific circumstances require, and what has and has not worked before to develop strategies that work.